1. Field of the Invention
The present invention relates to a magnetic recording-reproducing device, and more particularly, to a tape cartridge mounting mechanism for reliable mounting of a cartridge in which a magnetic tape is contained.
2. Description of Related Art
A conventional magnetic recording-producing device will be explained with reference to FIG. 16 giving a plan view of the device, FIG. 17A which is a sectional view taken along line A--A of FIG. 16, and FIG. 17B which is a side view showing a major portion of FIG. 17A.
First, in a conventional magnetic recording-reproducing device 21 (hereinafter referred to as the device 21), a pair of rail-like guide members 21b and 21c having a channel-shaped groove are mounted in opposite positions, upper and lower in the illustration, adjacently to the right side end shown in FIG. 16, on a base plate 21a disposed in the lower part.
Next, as shown in FIG. 17A, a pair of openings 21d are formed in a part of the base plate 21a in a portion in which the pair of guide members 21b and 21c are located.
In the right side end portion of the magnetic recording-reproducing device shown in FIG. 17A there is formed an insertion slot 21e for guiding a bottom plate 23c of a later-described cartridge 23 and inserting the cartridge 23 into the magnetic recording-reproducing device shown in FIG. 17A.
On the back face provided with the guide members 21b and 21c of the base plate 21a, a pair of leaf springs 22 having a great elastic force are mounted with one end fastened with a screw and the other end left as a free end. On the forward end of the free end of the leaf spring 22, a locking portion 22a is formed bent and a locking roller 22b is rotatably supported in the locking portion 22a.
The locking roller 22b is positioned in the opening 21d of the base plate 21a and is vertically movable on the support point of the screwed portion on one end within the opening 21d.
The cartridge 3 indicated by a two-dot chain line in the illustration is inserted at the insertion slot 21e into the device 21 while being guided by the guide members 21a and 21b. In the cartridge 23 is housed a magnetic tape 23a; and a pair of U-shaped guide grooves 23b are formed in both outer surfaces as seen in FIG. 17B. The pair of guide grooves 23b are guided by the rail-like guide members 21b and 21c, thus guiding the cartridge 23 into the device 21.
A cut away portion 23d is formed in a part of the bottom plate 23c which constitutes the guide groove 23b of the cartridge 23. Also in the cartridge 23a rotatable pinch roller 23f is disposed to transport the magnetic tape 23a laterally by means of a tape feed belt 23g.
Furthermore a magnetic head 24 and a tape transport roller 25 are disposed within the device 21.
The loading operation for loading the cartridge 23 in the device 21 is done as follows: first the forward end of the cartridge 23 is manually inserted in the direction of the arrow D into the insertion slot 21e of the device 21.
The forward end of the bottom plate 23c of the cartridge 23 hits against the locking roller 22b of the leaf spring 22.
As the cartridge 23 is further pressed inwardly with a greater force from this position into the device 21, the locking roller 22b is pushed downwardly by the bottom plate 12c of the cartridge 23, deflecting the leaf spring 22 downwardly until the locking roller 22b comes into elastic contact with the underside of the bottom plate 23c.
Then, as the cartridge 23 is pushed further into the device 21, the roller 22b that has been pushed downwardly to the underside of the bottom plate 23c comes in the cut away portion 23d of the cartridge 23, thus being moved upwardly into the cut away portion 23d with a great elastic force of the leaf spring 22. Then, as shown in FIG. 17A, the locking roller 22b makes elastic contact with one end of the cut away portion 23d, and the one end of the cut away portion 23d is pressed obliquely upwardly of the direction of the arrow C by the locking roller 22b, moving the cartridge 23 into contact with a stopper (not illustrated) in the device 21. The cartridge 23 is thus stopped to be loaded within the device 21.
At this time, the pinch roller 23f of the cartridge 23 is pressed into contact with the tape transport roller 25 in the device 21, so that the cartridge 23 will not further enter the device 21.
The pinch roller 23f is pressed in contact with the tape transport roller 25; in this state when the tape transport roller 25 is rotated, the pinch roller 23f also rotates, to thereby transport the magnetic tape 23a laterally via the tape feed belt 23g in the cartridge 23.
With the cartridge loaded in the device 21, the tape transport roller 25 is rotated by an instruction from an external computer not shown, thereby enabling recording a specific information in the magnetic tape 23a by means of the magnetic head 24 or reproducing the information from the magnetic tape 23a.
To eject the cartridge 23 out from the device 21, the rear end portion 23e of the cartridge 23 which protrudes out of the device 21 shown in FIG. 16 is manually pulled in the direction of the arrow E, and the locking roller 22b goes away downwardly from the cut away portion 23d of the cartridge 23, allowing the unloading of the cartridge 23 out of the device 21.
In the above-described conventional device 21, however, the loading and unloading of the cartridge are manually performed. Therefore, a considerable force (about 1.5 kgf to 3 kgf) is required for cartridge loading and unloading because of the presence of a great elastic force of the leaf spring 22. It is, therefore, difficult for a physically weak person to load and remove the cartridge 23.
If the cartridge 23 is forced recklessly into the device 21, the front side of the cartridge hits against a stopper (not illustrated) in the device 21, damaging both the cartridge and the stopper.
If the elastic force of the leaf spring 22 is reduced in an attempt to facilitate the loading and unloading of the cartridge 23, the force of the leaf spring for holding the cartridge 23 when the cartridge 23 is inserted into the device 21 will decrease, resulting in slipping of the pinch roller 23f in pressure contact with the tape transport roller 25, unstable feed of the magnetic tape 23a, and a failure of proper recording and reproducing.